Abstract: Methods are provided for forming a semiconductor device from a substrate comprising a bottom gate layer, a channel layer overlying the bottom gate layer, and a top gate structure formed over the channel layer. First, a hardmask comprising a first material interposed between a second material and a third material is deposited over a portion of the top gate structure. Then, the hardmask and top gate structure are encapsulated with an insulating material to form a spacer. A channel structure is formed from the channel layer, and the channel structure is disposed under the spacer. A bottom gate structure is formed from the bottom gate layer, and the bottom gate structure is disposed under the channel structure. Then, a source/drain contact is formed around the bottom gate structure.